harold



../75/200, .535," E2/@121455Z .Way 5? /X jyj @Bw l ma?? [n Zwnar AM,PHDTU-LITHD. C0. N.Y. SSSSSSSSSSSSSSSSS UNITED STATES PATENT OFFICE.

THOMAS G. HAROLD, OF BROOKLYN, NEW YORK, ASSIGNOR TO HIMSELF AND JAMESH. HAROLD, OF SAME PLACE.

GUARD FOR KEYI-IOLES.

Speccaton of Letters Patent No. 28,535, dated May 29, 1860.

To all whom it may concern:

Be it known that I, THOMAS G. HAROLD, of Brooklyn, in the county ofKings and State of New York, have invented, made, and applied to usecertain new and useful Improvements in Key-Guards to Prevent Burglarsfrom Picking Any Lock in l/Vhieh My Improvement May Be Placed; and I dohereby declare that the following is a full, clear, and exactdescription of the construction and operation of the same, referencebeing had to the annexed drawing, making part of this specification,wherein- Figure l is a plan of my improved guard in a position to enterany key hole. Fig. 2 is a plan showing my improvement in a lock with thelock plate in section and Fig. 3 is an elevation of a lock with myimproved guard placed therein. Fig. 4 is a plan showing my guard in aposition to be applied to a mortise lock.

Similar marks of reference indicate the same parts.

The nature of my said invention consists in a blocking piece a placedinto the key hole and afterward turned crosswise of the same as shown,so that it cannot be pushed out from the other side of the door. To holdthis blocking piece in position I attach the square bar Z) that isformed with the screwthread on its edges, and place thereon the slidingblocking piece 0 which is formed so as to slide into the key hole. Itwill now .be evident that when the blocking piece a is entered into akey hole and turned crosswise of the same and then the sliding blockingpiece c is pushed up into the key hole and the set screw l screwed upagainst the same the parts are held firmly together and that the keyhole is almost entirely stopped up and the sliding blocking piece o onthe square rod b sliding' into the key hole prevents the blocking piecea from being turned from the outside and that a burglar with his toolsfor picking locks might try in vain to open the same either by picks ornippers acting on the key barrel, because these blocks prevent the keybeing turned around.

When my improved key guard is applied to mortise locks the sliding blockc is formed as shown in Fig. t so as to allow for the thickness of thedoor. In all instances the key should be left in the lock and so turnedthat the look cannot be unlocked from the inside unless the guard betaken out. It desired however the sliding block o can be so formed thatit will ll up the upper part of the key hole and when so formed the keymust be taken out before inserting theguard.

Having thus described my said invention, what I claim and desire tosecure by Letters Patent is- The blocking piece a, fitted on the bar Z),in combination with the sliding blocking piece c, that enters the keyhole and prevents the piece a being turned or picks entered into the keyhole as set forth.

In witness whereof I have hereunto set my signature this fifth day ofApril 1860.

THOS. GEO. HAROLD.

Witnesses LEMUEL WV. SERRELL, CHAs. H. SMITH.

